How does this medication work? What will it do for me?

Diclofenac belongs to the class of medications known as non-steroidal anti-inflammatories (NSAIDs). It is used to reduce pain, swelling, and inflammation.

The diclofenac sodium tablet and suppository are used to relieve pain for people with rheumatoid arthritis, osteoarthritis, and degenerative joint diseases of the hip. The diclofenac potassium tablets are used for short-term relief of pain and inflammation, such as pain caused by sprains, surgery, dental work or menstrual cramps. The eye drop is used to reduce eye inflammation before and after eye surgery (e.g., cataract surgery) and in other cases of eye inflammation where infection is not present. The powder for oral solution is used for the treatment of migraine headaches.

This medication may be available under multiple brand names and/or in several different forms. Any specific brand name of this medication may not be available in all of the forms or approved for all of the conditions discussed here. As well, some forms of this medication may not be used for all of the conditions discussed here.

Your doctor may have suggested this medication for conditions other than those listed in these drug information articles. If you have not discussed this with your doctor or are not sure why you are being given this medication, speak to your doctor. Do not stop using this medication without consulting your doctor.

Do not give this medication to anyone else, even if they have the same symptoms as you do. It can be harmful for people to use this medication if their doctor has not prescribed it.

How should I use this medication?

Tablets: The usual adult dosage ranges from 50 mg to 100 mg daily. The immediate-release diclofenac sodium tablets are taken in 3 equally divided doses with food. Diclofenac potassium tablets are taken every 6 to 8 hours with food. The long-acting (sustained-release, or SR) tablets are taken in 1 or 2 daily doses with food or milk. The maximum recommended daily dose of diclofenac is 100 mg.

Tablets should be swallowed whole with some fluid. Do not crush or chew the tablets as this can change the way the medication is absorbed into your body. It may increase the risk of side effects, such as stomach irritation or bleeding.

Suppositories: The suppositories are usually used as a substitute for the last daily dose in a 50 mg or 100 mg strength, to a maximum total daily dose of 100 mg of diclofenac.

Many things can affect the dose of medication that a person needs, such as body weight, other medical conditions, and other medications. If your doctor has recommended a dose different from the ones listed here, do not change the way that you are using the medication without consulting your doctor.

It is important to use this medication exactly as prescribed by your doctor. If you miss a dose, skip the missed dose and continue with your regular dosing schedule. Do not administer a double dose to make up for a missed one. If you are not sure what to do after missing a dose, contact your doctor or pharmacist for advice.

Store this medication at room temperature, protect it from moisture, and keep it out of the reach of children.

Do not dispose of medications in wastewater (e.g. down the sink or in the toilet) or in household garbage. Ask your pharmacist how to dispose of medications that are no longer needed or have expired.

Who should NOT take this medication?

Do not take this medication if you:

are allergic to diclofenac or any ingredients of the medication

are breast-feeding

are in the third trimester of pregnancy (after 28 weeks)

are planning to have or have recently had heart bypass surgery

currently have or have recently had inflammatory diseases of the stomach and intestines, such as stomach or intestinal ulcer or ulcerative colitis

have bleeding in the brain or a bleeding disorder

have had an allergic reaction to ASA or other anti-inflammatory medications

have high levels of potassium in the blood

have severe uncontrolled heart failure

have severely impaired or deteriorating kidney function

have significant liver impairment or liver disease

Do not use diclofenac suppositories if you:

have any inflammatory lesions of the rectum or anus

have recently had rectal or anal bleeding

Do not give this medication to children or adolescents less than 16 years of age.

What side effects are possible with this medication?

Many medications can cause side effects. A side effect is an unwanted response to a medication when it is taken in normal doses. Side effects can be mild or severe, temporary or permanent.

The side effects listed below are not experienced by everyone who takes this medication. If you are concerned about side effects, discuss the risks and benefits of this medication with your doctor.

The following side effects have been reported by at least 1% of people taking this medication. Many of these side effects can be managed, and some may go away on their own over time.

Contact your doctor if you experience these side effects and they are severe or bothersome. Your pharmacist may be able to advise you on managing side effects.

abdominal or stomach cramps, pain, or discomfort (mild to moderate)

dizziness

drowsiness

headache (mild to moderate)

heartburn

nausea

sun sensitivity

Although most of these side effects listed below don't happen very often, they could lead to serious problems if you do not check with your doctor or seek medical attention.

Check with your doctor as soon as possible if any of the following side effects occur:

confusion

decreased hearing, any other change in hearing, or ringing or buzzing in ears

Stop taking the medication and seek immediate medical attention if any of the following occur:

large hive-like swellings on face, eyelids, mouth, lips, or tongue

severe and continuing nausea, heartburn, vomiting

signs of a serious allergic reaction (e.g., abdominal cramps, difficulty breathing, nausea and vomiting, or swelling of the face and throat)

signs of bleeding in the stomach (e.g., bloody, black, or tarry stools, spitting up of blood, vomiting blood or material that looks like coffee grounds)

signs of a heart attack (e.g., chest pain or pressure, pain extending through shoulder and arm, nausea and vomiting, sweating)

signs of a severe skin reaction such as blistering, peeling, a rash covering a large area of the body, a rash that spreads quickly, or a rash combined with fever or discomfort

Some people may experience side effects other than those listed. Check with your doctor if you notice any symptom that worries you while you are taking this medication.

Are there any other precautions or warnings for this medication?

Before you begin using a medication, be sure to inform your doctor of any medical conditions or allergies you may have, any medications you are taking, whether you are pregnant or breast-feeding, and any other significant facts about your health. These factors may affect how you should use this medication.

HEALTH CANADA ADVISORY

[October 6, 2014]

Health Canada has issued new restrictions concerning the use of diclofenac. To read the full Health Canada Advisory, visit Health Canada's web site at www.hc-sc.gc.ca.

Allergy: Some people who are allergic to other anti-inflammatory medications also experience allergic reactions to diclofenac. Before you take diclofenac, inform your doctor about any previous adverse reactions you have had to medications, especially ketorolac or ibuprofen. Contact your doctor at once if you experience signs of an allergic reaction, such as skin rash, itching, difficulty breathing, or swelling of the face and throat.

Breathing problems: People who have asthma, long term breathing problems, or allergic conditions such as hay fever or nasal polyps are more likely to experience difficulty breathing and allergic reactions, caused by NSAIDs. If you have a history of allergic reactions to other substances, or respiratory illness, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Drowsiness/reduced awareness: Some people have reported headache, dizziness, lightheadedness, and confusion while taking this medication. Avoid operating motor vehicles and doing other potentially hazardous activities until you have determined how this medication affects you.

Fertility: As with other NSAIDs, this medication may make it more difficult for a couple to conceive if the woman is taking diclofenac. Stopping the medication allows the body's chemistry to return to normal which often resolves this issue.

Fluid retention: Diclofenac may cause fluid retention and swelling, possibly worsening high blood pressure, congestive heart failure, or decreased heart function. If you have any of these conditions, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed. If you develop shortness of breath; fatigue; excessive weight gain; chest pain; or swelling of the legs, feet, or ankles while taking this medication, consult your doctor immediately.

Heart problems: Like other NSAID medications, diclofenac may increase the risk of heart attacks, strokes, and blood clots. The risk is greater with higher total daily doses and taking the medication for a long period of time. Due to this increased risk, people with the following conditions or risk factors should be closely monitored by their doctor if they use diclofenac:

congestive heart failure

diabetes

heart attack

heart disease

high blood pressure

high cholesterol

impaired kidney function

poor circulation

smoking

stroke

If you have any of these conditions, discuss with your doctor how this medication may affect your medical condition, how your medical condition may affect the dosing and effectiveness of this medication, and whether any special monitoring is needed.

Infection: This medication may hide the signs of an infection, such as a fever or generalized achiness.

Kidney function: Long-term use of diclofenac may lead to a higher risk of reduced kidney function. This is most common for people who already have kidney disease, liver disease, or heart failure; for people who are take diuretics (water pills); and for seniors. If you experience signs of decreasing kidney function, such as increased fluid retention or decreased amounts of urine being produced, see your doctor as soon as possible.

Liver function: This medication may cause liver problems. If you have a liver condition, you may need more frequent checkups with your doctor. If you develop signs of a liver problem (such as yellow skin or eyes, dark urine, pale stools, abdominal pain, or itchy skin), stop taking the medication and see your doctor as soon as possible.

Potassium levels: Diclofenac may increase the risk of high potassium levels in the blood, especially for seniors, people who have conditions such as diabetes or kidney failure, or those taking certain other types of medications. Your doctor may order blood tests periodically during long-term treatment to monitor the amount of potassium in your blood. People who have been diagnosed with having high potassium levels in their blood should not take this medication.

Stomach problems: Stomach ulcers, perforation, and bleeding from the stomach have been known to occur during treatment with diclofenac. These complications can occur at any time, and are sometimes severe enough to require immediate medical attention. The risk of ulcers and bleeding are increased for people taking higher doses of NSAIDs for longer periods of time.

Diclofenac should be taken under close medical supervision by people prone to irritation of the stomach and intestines, particularly those who have had a stomach ulcer, bloody stools, or diverticulosis or other inflammatory disease of the stomach or intestines (such as ulcerative colitis or Crohn's disease). In these cases, your doctor must weigh the benefits of treatment against the possible risks.

Stop taking the medication and contact your doctor immediately if you experience symptoms or signs suggestive of stomach ulcers or bleeding in the stomach (black, tarry stools). These reactions can occur at any time during treatment without warning.

Sun sensitivity: This medication may make your skin more sensitive to the sun. While you are using this medication, avoid excessive sun exposure, including tanning beds and sun lamps. If you experience sunburn with itching, swelling, and blistering, stop using this medication and contact your doctor.

Pregnancy: When diclofenac is taken during the last 3 months of pregnancy, there is an increased risk of the child developing heart problems and the mother having a longer labour to deliver the baby. If diclofenac is taken during the earlier stages of pregnancy, there is an increased risk of miscarriage. For these reasons, this medication is not recommended for use during pregnancy.

Breast-feeding: It is not known if diclofenac passes into breast milk. Due to the potential for harm to a baby if they are exposed to this medication, breast-feeding must be stopped before starting this medication.

Children: Diclofenac is not recommended for children under 16 years of age. The safety, effectiveness, and dosage of this medication for this age group have not been established.

Seniors: Seniors appear to have a higher risk of side effects with this medication. The lowest effective dosage should be used under close medical supervision.

What other drugs could interact with this medication?

There may be an interaction between diclofenac and any of the following:

If you are taking any of these medications, speak with your doctor or pharmacist. Depending on your specific circumstances, your doctor may want you to:

stop taking one of the medications,

change one of the medications to another,

change how you are taking one or both of the medications, or

leave everything as is.

An interaction between two medications does not always mean that you must stop taking one of them. Speak to your doctor about how any drug interactions are being managed or should be managed.

Medications other than those listed above may interact with this medication. Tell your doctor or prescriber about all prescription, over-the-counter (non-prescription), and herbal medications you are taking. Also tell them about any supplements you take. Since caffeine, alcohol, the nicotine from cigarettes, or street drugs can affect the action of many medications, you should let your prescriber know if you use them.